Affiliation: | aSt John's Institute of Dermatology, King's College London, Guy's Campus, London, UK;bDepartment of Dermatology, Poole General Hospital, Poole, Dorset, UK;cSt John's Institute of Dermatology, The Guy's and St Thomas’ NHS Foundation Trust, London, UK;dDepartment of Dermatology, Norfolk and Norwich University Hospital, Norwich, UK |